US officials will join talks in Geneva later this month on forming a Syrian constitutional committee, UN Syria envoy Staffan de Mistura told reporters on Thursday. The UN is also signaling movement in a process that had appeared at risk of stalling, Reuters reports. De Mistura plans to meet senior Russian, Turkish and Iranian officials early next week. The diplomat said he expected a similar meeting a week later with US, British, French, German and Jordanian officials. “We are seeing movement and we will keep seeking more of it,” the envoy said, adding, however, that he did not expect a major breakthrough.